Full 17x11" Calendar, High Resolution - Chandra X-ray Observatory

El Gordo
This young galaxy cluster, nicknamed “El Gordo” for
the “big” or “fat” one in Spanish, is a remarkable object.
Found about 7.2 billion light years away, El Gordo appears
to be the most massive, hottest, and most powerful
X-ray emitter of any known cluster at its distance
or beyond. In this composite image, X-rays are blue,
optical data from the Very Large Telescope are red,
green, and blue, and infrared emission from Spitzer is
red. The comet-like shape of the X-rays, along with optical
data, shows that El Gordo is actually two galaxy
clusters in the process of colliding at several million
miles per hour.
January 2013
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NGC 3627
NGC 3627 is a spiral galaxy located about 30 million
light years from Earth. A survey of 62 galaxies with
Chandra revealed that many of these galaxies contained
supermassive black holes that previously were
undetected. This study showed the value of X-ray observations
for fnding central black holes that have
relatively lower masses, as is the case for NGC 3627.
This composite image of NGC 3627 includes data from
Chandra (blue), Spitzer (red), as well as optical data
from Hubble and the Very Large Telescope (yellow).
February 2013
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Kepler’s
Supernova
Remnant
In 1604 A.D., a bright new object appeared in the night
sky. This object, which became known as Kepler’s supernova
after the famous astronomer Johannes Kepler
who studied it in detail, created an expanding remnant
of hot gas and high energy particles. A long Chandra
observation provided the basis for detailed computer
modeling of the interaction of the expanding debris
with the surrounding gas, and showed that the explosion
produced an amount of radioactive nickel roughly
equal to the mass of the Sun. In this image, the shock
front generated by the supernova is shown in cyan, and
the other colors show material heated by the explosion.
March 2013
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Full Field
Abell 520
Abell 520 is the site of a collision of massive galaxy
clusters located about 2.4 billion light years from Earth.
Data from Chandra (green) reveal large clouds of multimillion
degree gas in the clusters and provide evidence
for a collision. Optical data from Hubble and the
Canada-France-Hawaii Telescope appear white and
yellow, while starlight from galaxies within the clusters
is colored orange. This result confrms the presence
of a concentration of dark matter near the peak of the
X-ray emission, where very few galaxies are found.
The origin of this “dark core” is still a puzzle.
April 2013
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CAt’S EyE NGC 7662
NGC 7009 NGC 6826
Planetary Nebulas
When a star like our Sun runs out of hydrogen, it
puffs off its outer layers and leaves behind a hot core.
Winds from this core create a complex and graceful
flamentary shell called a planetary nebula (so called
because it looks like the disk of a planet when viewed
with a small telescope). This panel of images shows
four examples of planetary nebulas where Chandra’s
X-ray data (purple) have been combined with optical
images from Hubble (yellow and cyan). X-ray images
reveal clouds of multimillion-degree gas that have been
compressed and heated by these winds.
May 2013
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Abell 383
Two teams of astronomers used data from Chandra
and other telescopes to map the distribution of dark
matter in three dimensions in the galaxy cluster Abell
383. Analysis of the data shows that the dark matter
in Abell 383 is stretched out like a gigantic football
with the point of the football aligned close to the line
of sight. The Chandra X-ray data (purple) show the hot
gas, which is by far the dominant type of normal matter
in the cluster. Galaxies are shown with the optical
data from the Hubble, the Very Large Telescope, and
the Sloan Digital Sky Survey, colored in blue and white.
June 2013
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NGC 1929
This composite image shows a superbubble in the
Large Magellanic Cloud, a small satellite galaxy of the
Milky Way. Many new stars, some of them very massive,
are forming in the star cluster NGC 1929, which is
embedded in the nebula N44. The massive stars produce
intense radiation, expel matter at high speeds,
and race through their evolution to explode as supernovas.
The winds and supernova shock waves carve
out huge cavities called superbubbles in the surrounding
gas. X-rays from Chandra (blue) show hot regions
created by these winds and shocks, while infrared data
from Spitzer (red) outline where the dust and cooler
gas are found. Optical light from MPG/ESO (yellow)
shows where radiation from young stars is causing gas
in N44 to glow.
July 2013
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RCW 86
A supernova at the location in the sky of RCW 86
was witnessed by Chinese astronomers in 185 A.D..
Data from four space telescopes were combined to
determine the type of stellar explosion that produced
the supernova remnant RCW 86. X-ray data from
Chandra and XMM-Newton (blue and green) showed
that the remnant contains a large amount of iron,
pointing toward the explosion of a white dwarf star that
became unstable, and infrared data from Spitzer and
WISE (yellow and red) showed that the star exploded
in a nearly empty region of space, accounting for the
large diameter (85 light years) of the remnant.
August 2013
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Cygnus OB2
The Milky Way and other galaxies in the Universe
harbor many young clusters and associations that
each contain hundreds to thousands of hot, massive,
young stars known as O and B stars. The star cluster
Cygnus OB2 contains about 2,000 of these stars at a
relatively nearby distance to Earth of about 5,000 light
years. Chandra observations have helped to fnd the
young stars in the dusty environment of the cluster,
and provided evidence for a range of ages for the stars
(two million to fve million years). In this image, X-rays
from Chandra (blue) have been combined with Spitzer
data (red) and optical emission (orange).
September 2013
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M83
In 1957, a supernova was discovered in the spiral galaxy
M83. Since then, astronomers have been able to
detect the debris of the explosion, known as SN 1957D,
in both radio and optical wavelengths. However, until a
long observation with Chandra—totaling nearly 8 and
½ days of time—astronomers were not able to detect
X-rays from the remnant. The new X-ray data from
Chandra suggest that SN 1957D contains a rapidly rotating
neutron star, or pulsar. If confrmed, it would be
one of the youngest known pulsars. The supernova is
the blue X-ray source in the middle of the box.
October 2013
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30 Doradus
Located 160,000 light years away in the Large Magellanic
Cloud, a satellite galaxy of the Milky Way, 30 Doradus
is one of the largest star-forming regions close
to our galaxy. This composite of 30 Doradus (a.k.a., the
Tarantula Nebula) contains data from Chandra (blue),
Hubble (green), and Spitzer (red). At the center of 30
Doradus, thousands of massive stars are blowing off
material and producing intense radiation along with
powerful winds. Chandra detects gas that has been
heated to millions of degrees by these stellar winds
and also by supernova explosions. The X-rays come
from shock fronts, similar to sonic booms, formed by
this high-energy stellar activity.
November 2013
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Full Field
Musket Ball
A composite image of the 700 million year old “Musket
Ball” cluster shows how hot gas has been wrenched
apart from dark matter in a collision between clusters
containing thousands of galaxies. This separation occurs
because dark matter, unlike the particles of hot
gas, is essentially frictionless. It has been observed in
a few other clusters and is the most direct proof yet of
the existence of dark matter. Chandra detects the normal
matter as hot gas (red-purple), while optical emission
from several telescopes reveals the presence of
dark matter through the effect of gravitational lensing
(blue). Hubble optical data also show galaxies which
appear yellow and white.
December 2013
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